Re: Question…what was the last production model opposed twin? Home › Forum › Ask A Member › Question…what was the last production model opposed twin? › Re: Question…what was the last production model opposed twin? amullerReplies: 1055Topics: 163 May 21, 2017 at 3:30 pm #58104 quote melugin: Did OMC build a Cushman motor which was an air cooled opposed? Mid seventies or so twin going thru clutch and gearbox. Yes, that was a 4-stroke with overhead valves and hydraulic lifters. There was also a single. A rather sophisticated engine.